This power supply was featured in the December 1973 issue of Radio Electronics magazine. This type of circuit was used at the time to power tube televisions.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...